Doctors still don’t understand what causes multiple sclerosis, but there are interesting data that suggest that genetics, a person’s environment, and possibly even a virus may play a role.
How Does the Environment Affect a Person’s Risk of Multiple Sclerosis?
Epidemiological data show several interesting trends regarding multiple sclerosis:
- Different populations and ethnic groups have a markedly different prevalence of MS. The disease is especially common in Scotland, Scandinavia, and throughout northern Europe. In the U.S. the prevalence of MS is higher in whites than in other racial groups.
- Studies show that MS is more common in certain parts of the world, but if you move from an area with higher risk to one of lower risk, you acquire the risk of your new home if the move occurs prior to adolescence. Such data suggest that exposure to some environmental agent encountered before puberty may predispose a person to MS.
- Moreover, MS is a disease of temperate climates. In both hemispheres, its prevalence increases with distance from the equator.
Also there have been “epidemics” of MS — for example, the group of people living off the coast of Denmark after WWII, suggesting an environmental cause.